1. Field of the Invention
The present invention pertains to a housing that encloses the electronic control circuitry of an appliance. In particular, the present invention pertains to a housing that protects the motor control circuitry of a household appliance from moisture, dust and dirt where the housing has been specifically designed to facilitate assembly of the motor control circuit board into the housing so that electric terminals of the circuit board are accessible from the exterior of the housing. In addition, the housing is specifically designed to be easily attached into the interior of the appliance and removed if necessary. When attached to the interior of the appliance, the electric terminals of the circuit board are easily accessible from the exterior of the housing for attachment of the appliance wiring plugs to the circuit board electric terminals with the housing being specifically designed to facilitate the attachment of the appliance wiring plugs.
2. Related Art
Home appliances typically have their control circuitry enclosed in a protective housing that isolates the circuitry from moisture, dust and dirt. The control circuitry of the appliance is typically assembled into the housing by the appliance manufacturer. The housing with the installed circuitry is then assembled into the appliance. The wiring of the appliance is then connected to the control circuitry, typically by extending the wiring of the appliance into the interior of the circuitry housing and connecting plugs at the ends of the appliance wiring to electric terminals on a circuit board mounted in the housing. A separate cover is then attached to the housing to protect the electric terminals and the connected plugs from moisture, dust and dirt.
The prior art appliance control circuitry housings have been found to be disadvantaged in that they typically require the control circuit board of the appliance to be mounted on a separate frame before attaching the circuit board to the interior of the housing. The circuit board is typically attached to the frame which in turn is attached to the interior of the housing in securing the control circuit board to the housing. This requires that the housing actually be a two-part structure, the housing itself and the frame for the circuit board. In addition, the separate cover of the housing that covers over the circuit board electric terminals and the appliance wiring plugs connected to those terminals is a third part of the housing. Thus, the three pieces required of prior art control circuit housings increased their manufacturing cost.
In addition, the prior art control circuitry housing is usually attached to the interior of the appliance prior to the appliance wiring plugs being attached to the electric terminals on the control circuit board. With the housing attached to the appliance interior, it is often difficult to access the electric terminals on the circuit board in attaching the appliance wiring plugs to the terminals, making assembly of the appliance difficult.
Furthermore, because a secure attachment of the control circuitry housing to the interior of the appliance is necessary for the housing to remain secured to the appliance when the appliance is shipped, it is often difficult to remove the control circuitry housing from the interior of the appliance when servicing of the circuitry is needed.
What is needed to overcome the disadvantages of prior art appliance control circuitry housings described above is a control circuitry housing that can have the control circuit board assembled to the housing without requiring additional housing parts such as a frame and separate cover, a housing that provides easy access to the electric terminals of the circuitry once the circuit board is attached to the housing to facilitate the attachment of the appliance wiring plugs to the electric terminals, that provides adequate ventilation of the circuit board heat sink to avoid any heat-related failures of the appliance circuitry, that provides protection to the circuit board electric terminals and the attached appliance wiring plugs from moisture, dirt and dust without requiring additional parts of the housing, and a housing that is easily attached and removed from the interior of the appliance when servicing is needed.